Forming holes in rubber articles



June 9, 192,5.. v 1,541,119

w. DE ausl-IA Pomme Hows 1N Rusn ARTICLES Filed oct. 27, 192'1 '2sheets-sheet 2 WILLIAM DE Puel-IA INVENTOR Patented June 9, 19250UNi'rsn s'rATss PATENT oFFicE.

WILLIAM DE RUSHA, OF MILWAJ'KEE, WISCONSIN,

ASSIGNOR, BY M'ESNE ASSIGN- MENTS, TO THE FISK RUBBER COMPANY, OFCHICOPEE FALLS, MASSACHUSETTS, A CORPORATION 0F MASSACHUSETTS.

FORMING HOLES IN RUBBER ARTICLES.

Application inea october 27, 1921. serial No. 510,940.

To all whom it may concern:

Be it known that a citizen of the United States, and a res of Milwaukee,in the I, WiLLiAM DE RUSHA,

ident county of Milwaukee following is a speciiication.

My invention relates to forming holes in rubber articles and theprincipal object of my invention is to provide a new proved method offorming such particularly for forming an inner tube. ing thisspecification and forming a thereof I have shown, for purposes oftration one forni which my invention assume. In these drawings:

Figure 1 represents force the valve hole of an inner tube,

Figure 2 shows this pad with a punched through the fabric and beforapplication of the rubber ply thereto,

and irnholes and the valve hole in In the drawings accompany partillusmay a plan view of theV reinforcing pads commonly used to rein-,hole ethe Figure 3 shows the pad after the application of the rubberply,

Figure 4 illustrates the pad after a plus has been pushed through thehole in the fabric in a direction to carry the rubber through with it,

ply

Figure 5 illustrates the pad of Figure 4 after the inner-tube stock hasbeen applied,

Figure 6 illustrates the completed article after vulcanization, whileFigure 7 illustrates an alternative method of punching the pad.

Referring t0 the drawings,

I have shown a valve pad comprising a plurality of layers of fabric 11backed by a In Figure 2 I have shown ply of rubber 12. the plies offabric assembled and provided with a hole 13 which may be formed in anysuitable ner as by punching.

In Figure 3 I manhave

lshown a continuous ply of rubber 12 applied 4to the punched fabricplies, while in F 4 I have shown a plug the hole 13 tocarry with itigure 14 forced through under tension the portion of the rubber ply 12which overlay the hole 13. In Figure 5 I have show nftlie manner thatsaid ru ber tends to move assembled pad on a mandrel 15 with the innertube stock 16 wrapped about it in such manner as to impart to thatportion of the stock lying over the plug 14 a tendency to flow from overthe plug. The tube thus mounted on the mandrel with the assembled valvepad in position is 'so'that the plug may be readily removed to leave inthe finished tube a hole which is in exactly the correct position and,because of the extension of the ply 12 through the hole in the fabric,is lined throughut with rubber and has no fabric exposed.

In the modification shown in Fi re 7 the hole is punched through the paafter the rubber ply has been addedr but other- Wise the process andproduct are the same.

I have disclosed herein one form which my invention may assume and amodification thereof but this disclosure is of course illustrative onlyand my invention is not limited thereto.

I claimt 1. The method of forming a hole in a rubber article whichcomprises cutting a hole at least part wayv through the reinforcing pad,inserting in said hole a plug which p'otrudes from the hole, pressingthe rubr of the article a ainst said plug in such from over said plug,and vulcanizing.

2. The method of forming valve holes in 14 and the similar portion ofthe l tubes which comprises placing an aperture'd reinforcin pad over aply of rubber, forcing the ru ber ply through the aperture of said pad,applying the tu e stock over said aperture and vulcanizing.

3. The method of forming valve holes in tubes which comprises placing anapertured reinforcing pad over an unbroken ply of raw rubber, insertinga plu in said hole to thereby force the; rubber p y through the apertureof asid pad, applying the tube stock over said aperture and plug andvulcanizing under pressure.

4. The method of forming valve'lioles in tubes which comprises forcing nply of rub- 5 ber through the opening of an apeitured reinforcing pad,retaining said ply in such assembled position applying tube stock oversaid assembly and vulcanizing under suicient pressure to causethe tubestock uml rubber ply to How from the aperture to form 1o n rubber linedpassage in the tube.

In testimony whereof I have signed my nume to the above specification.

WILLIAM DE RUSHA.

